Fiber-reinforced body, method for producing the body and pipe or tube sheet having the body

ABSTRACT

A body includes a ceramic material and is suitable for use in a heat exchanger and for conducting fluids. An outer side of the body is at least partially encompassed by at least two fiber bundles in the longitudinal and/or circumferential direction and force-lockingly connected thereto. The fiber bundles are pre-tensioned and neighboring sections of the fiber bundles are disposed at a predetermined distance. A method for producing a body includes providing a body including a ceramic material and being suitable for use in a heat exchanger and for conducting fluids, and encompassing at least sections of the outer side of the body with at least two fiber bundles under a predetermined pretension forming a force-locking connection and with neighboring sections of the fiber bundle disposed at a predetermined distance. A heat exchanger pipe or tube sheet includes the body.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation, under 35 U.S.C. §120, of copending InternationalApplication No. PCT/EP2010/067211, filed Nov. 10, 2010, which designatedthe United States; this application also claims the priority, under 35U.S.C. §119, of German Patent Application DE 10 2009 054 910.2, filedDec. 17, 2009; the prior applications are herewith incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a fiber-reinforced body, a method forthe production thereof and a pipe or a pipe bottom or tube sheet havingthe body in a heat exchanger.

Components made from ceramic material, such as silicon carbide pipes,are often used in heat exchangers. Since they are formed of ceramicmaterials, leak-proof silicon carbide pipes are prone to brittlefracture. In the event of mechanical failure, the pipes fracturecatastrophically, i.e. into fractured sections. The pipe loses itsintegrity. A heat exchanger that has been made from pipes of that kindmay be destroyed by a fracture of that nature, as corrosive acids reachthe heat exchanger's service compartment, which is not protected againstcorrosion. In addition, further damage may occur in the cooling systemor the heating system to which the heat exchanger is connected.

SUMMARY OF THE INVENTION

It is accordingly an object of the invention to provide afiber-reinforced body, a method for producing the body and a pipe ortube sheet having the body, which overcome the hereinafore-mentioneddisadvantages of the heretofore-known devices and methods of thisgeneral type and which provide a material that is immune to catastrophicbrittle fracture.

With the foregoing and other objects in view there is provided, inaccordance with the invention, a body, comprising a ceramic materialwhich is suitable for use in a heat exchanger and for conducting fluids.The outer side of the body is at least partially encompassed by at leasttwo fiber bundles in the longitudinal direction and/or thecircumferential direction and force-lockingly connected thereto. Thefiber bundles are pre-tensioned. Neighboring sections of the fiberbundles are disposed at a predetermined distance. Reinforcing the bodythrough the use of the fiber bundles means that it becomes more immuneto brittle fracture and its pressure resistance and load-bearingcapacity are increased. A force-locking connection is one which connectstwo elements together by force external to the elements, as opposed to aform-locking connection which is provided by the shapes of the elementsthemselves.

The fiber reinforcement improves the properties of bodies as follows: Itprovides an increase in bursting pressure, the body becomes more immuneto brittle fracture, steam hammering and unpermitted exceeding of theoperating pressure. Even if fluids are conducted through thefiber-reinforced body during routine operation and a longitudinal crackappears therein, as a result of its age, for example, improper use oroverstress, this body does not exhibit any significant leaks up to apredetermined differential pressure. The pushing out or breaking out offragments of the body is intercepted to a certain extent due to theencompassing of the body with fiber bundles, in such a way that a piecepushing or breaking out of the original form of the body is retained ina predetermined form by the surrounding pre-tensioned fiber bundle. Thebreaking out of pieces from the body and therefore the emergence oflarge quantities of fluid are prevented. The heat exchanger in which thebody is used can usually be further operated without interruption untilthere is a planned shutdown. The body according to the invention istherefore leak-proof to a certain extent, even in a defective state, incomparison with an unreinforced body.

In accordance with another feature of the invention, the body ispreferably a pipe-shaped body. Within the meaning of the presentinvention, a pipe-shaped body is particularly taken to mean a body whichpreferably has a circular cross-section and is open at the ends of itslongitudinal extension, in order to be suitable for conducting fluids.Alternatively, however, the pipe-shaped body may also exhibit a square,oval or other shaped cross-section. The longitudinal extension of thepipe-shaped body is preferably greater than its cross-section. Thepipe-shaped body is preferably a pipe with a circular cross-section.

Alternatively, in accordance with a further feature of the invention,the body is a cover, wherein a plurality of holes extends in thelongitudinal direction of the cover. A cover, in the context of thepresent invention, is taken to mean a body with a preferably circularcross-section, which does not exhibit a single cavity, but a pluralityof cavities. In order for it to be suitable for conducting fluids, thecover has a plurality of holes, which extend in the longitudinaldirection of the cover and therefore represent cavities. Within themeaning of the present invention, the cover is regarded as a pipe-shapedbody, the length dimension of which is not crossed or traversed by asingle cavity, but by a plurality of cavities, which may lead into asingle cavity within the longitudinal extension of the cover or maycontinuously extend separately along the longitudinal direction of thecover. The longitudinal extension of the cover is preferably smallerthan its cross-section. It may be so small, for example, that the coverexhibits the shape of a round disc or plate, which is crossed ortraversed by holes extending in the longitudinal direction. The entirecross section of the cover may exhibit a plurality of holes.Alternatively, it is also conceivable that only at least a partialsection exhibits a plurality of holes.

In accordance with an added preferred feature of the invention, thefiber bundles form a network. This means, for example, that the at leasttwo fiber bundles are inclined towards one another, at ±80° for example,to the longitudinal axis of the body.

The density of the network depends on the nature of the body'sapplication, the load to which the body is exposed and the strength anddimensions of the body. If it is expected that the body will break intosmaller fragments in case of a fracture, a dense network of fiberbundles is desirable. On the other hand, the greater use of materials infiber bundles also raises costs, so that the density of networked fiberbundles being used should be individually adapted to the desired effectswith regard to the resulting material costs.

In accordance with an additional preferred feature of the invention, theratio of the distance between neighboring fiber bundles to the diameterof the fiber bundles is between 5:1 and 10:1. It is a function of thebody's mechanical load. The body's thermal resistance in proportion tothe ratio is substantially unchanged. In each direction at an angle tothe longitudinal extension of the fiber bundles, comparatively thinfiber bundles and uncovered strips with a broad surface area alternateon the outer side of the body.

The at least two fiber bundles may encompass or reinforce the bodypartially or completely. A complete reinforcement is desirable wherebodies are subject to heavy loads. Alternatively, it may also beexpedient, out of cost considerations, for only those parts of the bodythat are subject to particularly heavy loads to be reinforced. In thecase of pipes, for example, end sections, in particular, which areconnected to other components, are areas in an apparatus such as a heatexchanger which are subject to a particular load or prone to fracturesand may require particular protection in the form of reinforcement. Ifthe body is a temperature-loaded component, it should furthermore betaken into consideration that the body and fiber bundle may havedifferent thermal expansion coefficients and the length and width of thefiber bundle configuration should be adapted accordingly. The fiberbundles should therefore be disposed in such a manner on the at leastone outer side of the body, that the body's thermal expansion can becompensated by the fiber bundles or can be allowed without leading tothe destruction of the body.

In accordance with yet another feature of the invention, the ceramicmaterial is preferably dense sintered silicon carbide. It is chosen forits outstanding properties such as, for example, high thermalconductivity, high strength, high corrosion resistance to acid and basemedia and high load-bearing capacity. The silicon carbide is preferablypressureless sintered silicon carbide, which exhibits extremely highcorrosion resistance to acid and base media, which it can likewisewithstand to very high temperatures, high temperature change resistance,high thermal conductivity, high wear resistance and a hardnessresembling that of diamond. As a further alternative, the siliconcarbide may be a liquid phase-sintered silicon carbide, which isproduced from silicon carbide and different oxide ceramics and isdistinguished by its great strength.

The silicon carbide may contain at least one ceramic or mineral fillermaterial, wherein the choice of filler materials is adapted to theapplication. Examples of filler materials are materials from the groupof naturally occurring flake graphite, artificially producedelectrographite, soot or carbon, graphite or carbon fibers orborocarbide. Furthermore, ceramic or mineral filler materials may beused in grain, platelet or fiber form, as silicates, carbonates,sulfates, oxides, glass or selected mixtures thereof.

In accordance with yet a further preferred feature of the invention, thefiber bundles are carbon fiber bundles. A carbon fiber bundle has goodtensile strength, corrosion resistance and stiffness, low breakingelongation and is resistant at the application temperatures of loadedbodies. The specific performance of the carbon fiber bundles means thatthe pre-tensioning of the reinforcement is retained, even if the pipe issubject to highly variable or dynamic loads. Due to the negative thermallongitudinal expansion coefficient of carbon fiber bundles, thereinforcement is further pre-tensioned in case of a temperature rise,the bursting and leak-tight pressure is greater at a higher temperaturethan at room temperature. The carbon fiber reinforcement improves theproperties of bodies, particularly in the case of silicon carbide pipes,as follows: an increase in bursting pressure is provided, the bodybecomes more immune to steam hammering and unpermitted exceeding of theoperating pressure, since the body's bursting pressure at roomtemperature is 30 to 40% greater depending on the dimensions, ascompared with a non-reinforced body. Other examples of fiber bundles areglass fiber bundles or aramid fiber bundles.

In accordance with yet an added preferred feature of the invention, theforce-locking connection between the fiber bundles and the outer side ofthe body is an adhesive system. It is used to fix the fiber bundles tothe body. The adhesive system is chosen from the group includingadhesives which are made up of phenolic resin, epoxy resin orpolysilazane-based resin. If necessary, the adhesive system may containa silicon or silicon carbide filler material. It is also referred to ascement in the present invention. The adhesive system may include one ormore of the adhesives mentioned earlier and/or cement. If necessary, theadhesive or cement may further contain a hardening catalyst and/or aplasticizer. Adhesives or cements of this kind are usuallyoxidation-resistant. These adhesives or cements also adhere well to botha ceramic material, such as silicon carbide, and also to fiber bundles,such as carbon fiber bundles, and are capable of wetting a fibereffectively.

The adhesive system is preferably a phenol resin. More preferably, thephenol resin is a resol. Alternatively, the phenol resin may also be anovolac. Resin systems containing bisphenol A-diglycidyl ether orbisphenol F-diglycidyl ether are also suitable as epoxy resin. Inparticular, resin systems which contain methyl hexahydrophthalic acidanhydride, particularly in a quantity of 25 to 50% by weight, inaddition to more than 50% by weight bisphenol A-diglycidyl ether orbisphenol F-diglycidyl ether, based on the total weight in each case,are suitable as epoxy resin systems. A polysilazane resin system mayalso preferably be used as the adhesive system.

All of the adhesives mentioned above may further contain silicon orsilicon carbide as the filler material. The plasticity of the cement maybe adjusted to the desired adhesive bond through the use of theproportion of resin in the mixture or by adding plasticizer. The use ofcement containing silicon or silicon carbide alongside the resinadhesive is particularly suitable when it is applied to the fiberbundle. Through impregnation of the fiber bundle with the cement andsubsequent burning, silicon with carbon fibers can form silicon carbideor with silicon carbide as the filler material the impregnated and burntcarbon fiber exhibits silicon carbide.

The choice of adhesive system depends on the desired bond and cruciallyon the nature of the application of the body according to the invention.When selecting an epoxy resin as the adhesive system, which is appliedto the body or with which the fiber bundle is impregnated and hardened,a greater reduction in tension is not possible, due for example to thebrittleness of the hardened layer, a rigid connection is retainedbetween the fiber bundles and the body. By using plasticizers, thisconnection can be made deformable, in order to intercept possible shearstresses or different expansions of the fiber bundles and the bodyduring temperature changes, for example.

The body and the fiber bundles may be fixed through the use of anadhesive system, wherein the adhesive system is either applied to thebody, the fiber bundles or both and then hardened or burnt.Alternatively, the body and the fiber bundles may each be provided withan adhesive system independently of one another and fixed to oneanother. The adhesive systems applied in this case may be identical ordifferent. The choice depends on the adhesive power required and may beappropriately chosen and adapted by the person skilled in the art.

The adhesive system may be disposed at points or in sections between thebody and the fiber bundles, so that a number of predetermined points onthe fiber bundle are fixed to the body. Alternatively, the fiber bundlesmay be completely fixed to the body through the use of adhesion. Thefiber bundles are preferably completely fixed to the body.

The fiber bundles may exist in the form of a yarn. This is particularlytrue when the fiber bundles are wound onto bodies and possibly fixedthere. A yarn is taken to be a fiber bundle made up of a plurality offilaments. The yarn may exhibit sections running straight, diagonallyand/or in a curved fashion. In order to create a network, at least one,preferably two, yarns intersect at predetermined points at a desiredangle, preferably ±80°. Yarn sections may also be intertwined, meshed orintegrated in some other way.

Otherwise, the fiber bundles may also be in the form of braiding, laidwebs, knitted fabric, woven fabrics or interlaced yarns, preferablywoven fabrics or interlaced yarns, which are pulled onto the body in apre-tensioned state and fixed where necessary. Braiding is taken to meanan area-measured fabric, which is produced through the intersection ofbraid/thread systems running diagonally in opposite directions, whereinthe braided threads cross one another at an adjustable angle to thefabric edge. A laid web is regarded as an area-measured fabric made upof one or more stretched, superimposed thread systems with differentorientation directions, with or without fixing of the points ofintersection. A knitted fabric is an area-measured fabric, in which themeshes are formed individually and consecutively from a horizontallylaid thread, in addition further thread systems can also be incorporatedfor reinforcement. An area-measured fabric containing at least twothread systems usually crossing one another at right angles is regardedas a woven fabric. An interlaced yarn is an area-measured fabric, whichis produced from one or more threads through the simultaneous formationof meshes in a longitudinal direction. Further threads may, of course,be incorporated for additional reinforcement. At least one fiber bundleof a predetermined length is regarded as the thread in this case. Athread system is taken to mean several threads.

It is, of course, also possible, when the fiber bundles are disposed inthe form of a woven fabric or interlaced yarn, for the woven fabric orinterlaced yarn to be longer than the body, so that where necessary thewoven fabric or interlaced yarn protects the connection of the body to afurther component through its configuration on the body.

With the objects of the invention in view, there is also provided amethod for producing a body. The method comprises:

-   -   a) providing a body which includes a ceramic material and is        suitable for use in a heat exchanger and for conducting fluids;        and    -   b) encompassing at least sections of the outer side of the body        by at least two fiber bundles under a predetermined pre-tension        forming a force-locking connection, wherein neighboring sections        of the fiber bundle are disposed at a predetermined distance.

With this method, the body's pressure resistance usually required inequipment production is achieved by reinforcing the body with fiberbundles. The pre-tensioning used according to the invention may beadjusted by a person skilled in the art according to the fiber materialand area of application of the body.

In accordance with another mode of the invention, step b) may preferablyinclude encompassing at least sections of the outer side of the body byat least two fiber bundles, so that the fiber bundles are in the form ofa network. Alternatively, it is conceivable for the fiber bundles to bepulled around the body in the form of an area-measured fabric. Step b)is preferably carried out in such a way that the ratio of the distancebetween neighboring fiber bundles and the diameter of the fiber bundlesis between 5:1 and 10:1. The increase in the strength of the body isthereby achieved with a relatively small covering of the outer side orsurface of the body.

In accordance with a further preferred mode of the invention, beforestep b) an adhesive system is at least partially applied to the fiberbundle and/or the body and then hardened or burned. The fiber bundleconfiguration is thereby fixed to the outer side of the body. Theadhesive system used for fixing is preferably chosen from the groupincluding adhesives, which are formed from phenol resin, epoxy resin orpolysilazane-based resin and are possibly mixed with silicon and siliconcarbide filler material. Adhesive systems of this kind are readilyworkable and can be adapted to the shape of the body or are well-suitedto the impregnation of a fiber, they exhibit good adhesive strength to aceramic material such as silicon carbide and many types of fibers and,in particular, to a carbon fiber, following thermal hardening orburning.

The body and the fiber bundles may be fixed through the use of anadhesive system, wherein the adhesive system is applied either to thebody, the fiber bundle or to both and then hardened or burned. Anadhesive system which does not contain silicon or silicon carbide as thefiller material is hardened, while an adhesive system containing siliconor silicon carbide as the filler material is burnt. Hardening ispreferably carried out at temperatures between 120 and 180° C. for oneto up to two hours, in a pressureless environment or at pressures ofbetween 0.5 and 1.5 bar. At high temperatures, i.e. around 170 to 180°C., a hardening time of up to 15 minutes is generally sufficient. Thehigher the temperature is, the shorter the hardening time. If theadhesive system contains a hardening catalyst, the hardening may alsotake place at room temperature. Burning is preferably carried out attemperatures of over 1500° C. for up to 2 hours, in a pressurelessenvironment or at pressures of 0.5 to 1.5 bar. Following the hardeningof the adhesive or burning of the cement, the fiber bundles are disposedon the outer side of the body.

The body and the fiber bundles may each be provided with an adhesive orcement independently of one another and then fixed. The adhesives orcements applied may be identical or different in this case. A personskilled in the art may select suitable adhesives or cements, whichadhere well to one another.

In accordance with an added preferred mode of the method of theinvention, the fiber bundles are impregnated with an adhesive or cement,after which they are hardened or burned and finally disposed on thebody.

The adhesive system may be disposed between the body and fiber bundlesat points or in sections, so that a number of predetermined points ofthe fiber bundles are fixed to the body. Alternatively, the fiberbundles may be completely fixed to the body through the use of adhesiveor cement. The fiber bundles are preferably completely fixed to thebody.

The body used in the method according to the invention is preferably apipe-shaped body or cover, wherein a plurality of holes extends in thelongitudinal direction of the cover.

The ceramic material used in the method according to the invention ispreferably silicon carbide, which optionally contains at least oneceramic or mineral filler material.

In the method according to the invention, the fiber bundles arepreferably carbon fiber bundles. The carbon fiber bundles may be woundaround the body in a predetermined pre-tensioned state in the form of ayarn. Alternatively, the carbon fiber bundles may exist in the form ofbraiding, laid webs, knitted fabric, woven fabric or interlaced yarns,preferably woven fabric or interlaced yarns, and are drawn over the atleast one outer side of the body possibly provided with a hardenedadhesive or burnt cement. On the other hand, it is conceivable for thecarbon fiber bundle to be used in the method according to the inventionas fiber bundles provided with hardened adhesive or burnt cement.Particularly in the case of carbon fiber bundles, the use of cement withsilicon as the filler material is suitable, since silicon can react withthe carbon fiber during the burning process to produce silicon carbideand a firmer bond between the carbon fiber and the cement can thereby beachieved.

With the objects of the invention in view, there is concomitantlyprovided a pipe, pipe base or tube sheet in a heat exchanger, comprisingthe body according to the invention.

The body according to the invention is particularly suitable for use asa pipe, for example for heat exchangers where there is increasedmechanical stress and/or extremely corrosive media and solvents, andalso for all other components subject to pressure and temperature loads.It is a particularly ideal material for the construction of heatexchangers, because it is highly thermally conductive,pressure-resistant and immune to brittle fracture. The body according tothe invention is particularly preferably used as the pipe in a heatexchanger, because it is erosion-resistant and permits high flowvelocities and a self-cleaning effect of the pipe is thereforeachievable through fast-flowing media, which may be charged withparticles. In addition or alternatively, the body according to theinvention is preferably used as a pipe base or tube sheet in a heatexchanger. In assembled form, several pipe-shaped bodies and coversaccording to the invention are used as a pipe bundle heat exchanger.

A heat exchanger including a body according to the invention exhibitsthe following structure in accordance with German Patent Application DE197 14 423, for example. The heat exchanger includes a casing, a basewith supports, a spacer to create a distributor space, a distributorbase with the inner and outer pipe bases or tube sheets and pipesdisposed in the bores of the pipe bases and sealed therein through theuse of a sealant. The base and casing are customarily screw-fastened,wherein the spacer is inserted in between to create the distributorspace. The inner pipe base of the distributor base is smaller indiameter than the inner casing diameter. The outer pipe base is greaterin diameter and therefore assumes the sealing function between thecasing and the distributor space. The pipes represent the body accordingto the invention in the form of a pipe made from pressureless sinteredsilicon carbide, the outer side of which is encompassed by pre-tensionedcarbon fiber bundles. If there is a temperature increase, thepre-tensioning of the reinforcement is advantageously increased by thenegative thermal expansion coefficient of the carbon fiber. The heatexchanger then works more reliably and safely. In addition oralternatively, the outer and/or inner pipe base may further includepressureless sintered silicon carbide, which is encompassed bypre-tensioned carbon fiber bundles. Alternatively, in addition to thesilicon carbide pipe and the network of carbon fiber bundles, the pipesfurther exhibit one of the adhesive systems described above for fixingthe two elements. If the adhesive system is oxidation-resistant,oxidation media may also be used for cooling or heating in the servicespace of the heat exchanger constructed through the use thereof.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin a fiber-reinforced body, a method for producing the body and a pipeor pipe base or tube sheet having the body, it is nevertheless notintended to be limited to the details shown, since various modificationsand structural changes may be made therein without departing from thespirit of the invention and within the scope and range of equivalents ofthe claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a diagrammatic, side-elevational view of a body according tothe invention;

FIG. 2 is a partially longitudinal-sectional, side-elevational view ofthe body according to the invention shown in FIG. 1;

FIG. 3 is an enlarged, longitudinal-sectional view of a portion III-IIIenclosed by a dot-dash line in FIG. 2; and

FIG. 4 is a longitudinal-sectional view of a portion of a further bodyaccording to the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures of the drawings in detail and first,particularly, to FIG. 1 thereof, there is seen a diagrammatic side viewof a body assembly 1 according to the invention. The body assembly 1includes a smooth-walled body or pipe 3 made from pressureless sinteredsilicon carbide. The pipe 3 has an opening at both of its two ends 5, 7,so that it is suitable for conducting fluids. The pipe 3 has yarns 9made from carbon fiber bundles wound around it, with the bundles beinghighly pre-tensioned and acting as reinforcement for the pipe 3. Theyarns 9 have a non-illustrated phenol resin layer, which acts as anadhesive layer. The yarns 9 are wound around the pipe 3 in such a mannerthat they cross at predetermined points, so that they form a network.

A further diagrammatic side view of the body 1 according to theinvention shown in FIG. 1, is depicted in FIG. 2. In FIG. 2, the samereference numbers are used for the same elements as in FIG. 1. In FIG.2, the smooth-walled pipe 3 is likewise shown with the pipe ends 5, 7and with the pipe having yarns 9 made from pre-tensioned carbon fiberbundles with a phenol resin layer wound around it. A part of the pipe,which is shown in cross-section, further shows a pipe wall 13 of thepipe 3, which has an inner side 14 and an outer side 15. The inner side14 delimits a hollow cavity 11 of the pipe 3, which is unrestricted inthe longitudinal direction and ends in an opening at each of the pipeends 5, 7. A fluid may be conducted through the cavity 11 which islimited by the inner side 14. The yarns 9 are disposed on the outer side15 of the pipe wall 13.

FIG. 3 shows an enlarged portion of FIG. 2, which is enclosed in FIG. 2by a dot-dash line and marked with reference symbols III-III. In FIG. 3,the same reference numbers are used for the same elements as in FIG. 2.It can be seen from the enlarged view that the yarns 9 are disposed onthe outer side 15 of the pipe wall 13, while the cavity 11 is formed bythe inner side 14 of the pipe wall 13.

FIG. 4 shows a cross section through a portion of a further bodyassembly 41 according to the invention. The body assembly 41 accordingto the invention has a body or smooth-walled pipe 43 made frompressureless sintered silicon carbide. The pipe 43 has a pipe wall 413,which has an inner side 414 and an outer side 415. An adhesive 417 madefrom phenol resin is disposed on the outer side 415 of the pipe wall413, on which yarns 49 made from carbon fibers are disposed. Theadhesive 417 is only located in those areas of the outer side 415 of thepipe 413 in which the yarns 49 are disposed. The adhesive 417 is used tofix the yarns 49 to the outside 415 of the pipe wall 413. The pipe has acavity 411, which is limited by the inner side 414 of the pipe wall 413of the pipe 43.

1. A body assembly, comprising: a ceramic material body configured foruse in a heat exchanger and for conducting fluids, said body having anouter side and longitudinal and circumferential directions; at least twofiber bundles at least partially encompassing and force-lockinglyconnected to said outer side of said body in at least one of saidlongitudinal and circumferential directions; and said fiber bundlesbeing pre-tensioned and having neighboring sections disposed at apredetermined distance from each other.
 2. The body assembly accordingto claim 1, wherein said body is a pipe-shaped body or cover having aplurality of holes extending in said longitudinal direction, and saidfiber bundles form a network.
 3. The body assembly according to claim 1,wherein said fiber bundles have a diameter, and a ratio of saidpredetermined distance between neighboring sections of said fiberbundles and said diameter of said fiber bundles is between 5:1 and 10:1.4. The body assembly according to claim 1, wherein said fiber bundlesare carbon fiber bundles.
 5. The body assembly according to claim 1,wherein said ceramic material is dense sintered silicon carbide.
 6. Thebody assembly according to claim 5, wherein said dense sintered siliconcarbide contains at least one ceramic or mineral filler material.
 7. Thebody assembly according to claim 1, wherein said force-lockingconnection between said fiber bundles and said outer side is an adhesivesystem selected from the group of adhesives consisting of phenolicresin, epoxy resin and polysilazane-based resin.
 8. The body assemblyaccording to claim 7, wherein said adhesive system is mixed with siliconand silicon carbide filler material.
 9. A method for the production of abody assembly, the method comprising the following steps: a) providing abody including a ceramic material and being configured for use in a heatexchanger and for conducting fluids; and b) encompassing at leastsections of an outer side of the body with at least two fiber bundlesunder a predetermined pre-tension forming a force-locking connection andwith neighboring sections of the fiber bundle disposed at apredetermined distance from each other.
 10. The method according toclaim 9, which further comprises carrying out step b) by encompassing atleast sections of the outer side of the body with at least two fiberbundles in the form of a network.
 11. The method according to claim 9,which further comprises carrying out step b) by encompassing at leastsections of the outer side of the body with at least two fiber bundleshaving a ratio of the predetermined distance between neighboringsections of the fiber bundles and a diameter of the fiber bundles ofbetween 5:1 and 10:1.
 12. The method according to claim 9, which furthercomprises, before step b), at least partially applying an adhesivesystem to the body and/or the fiber bundle and then hardening or burningthe adhesive system.
 13. The method according to claim 12, which furthercomprises selecting the adhesive system from the group of adhesivesconsisting of phenolic resin, epoxy resin and polysilazane-based resin.14. The method according to claim 13, which further comprises mixing theadhesives with silicon and silicon carbide filler material.
 15. Themethod according to claim 9, wherein the body is a pipe-shaped body orcover having a plurality of holes extending in longitudinal direction ofthe cover.
 16. The method according to claim 9, wherein the fiberbundles are carbon fiber bundles.
 17. The method according to claim 9,wherein the ceramic material is dense sintered silicon carbide.
 18. Themethod according to claim 17, wherein the dense sintered silicon carbidecontains at least one ceramic or mineral filler material.
 19. A heatexchanger pipe or tube sheet, comprising: a body assembly according toclaim 1.